Valve for engines.



J. B. ALLFREE;

VALVE FOR ENGINES.

APPLICATION I'ILED JAN. 9, 1908.

Patented June 7, .1910.

3 SHEETS-SHEET 1.

amveul'oz attain;

DREW a GRANAM c0 PHOTO-LITNOGMPN J. B. ALLPREE.

VALVE FOB. ENGINES.

APPLICATION FILED JAN. 9, 1908. 960,61 6.

Patented June 7, 1910.

3 SHBETSSHEET 2.

ANDREW B. GRAHAM c0. PHOTO-LITHOGRAPHERS, WASHWGYON. D. C

J. B. ALLPREE.

VALVE FOR ENGINES.

APPLIGATION FILED JAN. 9, 190a.

Patented June 7,1910.

3 SHEETS-SHEET 3.

we muses ANDREW a. GRAHAM C0 PHOYO-LITHOGRAPHERS, wAsmHsIuN. D. c.

- mas T tion.

VALVE FOR ENGINES.

To all whom it may concern:

Be it known that I, JAMES B. ALLFREE, a citizen of the United States,residing at Chicago, in the county of Cook and State of Illinois, haveinvented certain new and useful Improvements in Valves for Engines, ofwhich the following is a specification.

The object of the present invention is to improve the valve arrangementof steam or like engines and the embodiment thereof illustratedconstitutes a modification of the construction shown in U. S. Patent No.770,671, issued to me September 20, 1904, and my application filedSeptember 25, 1907, Serial No. 394,517.

My invention contemplates an arrangement of cylinder and steam chestwith short live steam and exhaust ports with cooperating main andcompression regulating valves so arranged as to insure a more economical distribution and use of the steam, in the cylinder thanotherwise. This result is attained by provisions hereinafter describedwhereby the valves in controlling, the admission, exhaust andcompression of steam provide for the highest rate of expansion, thegreatest mean eifective pressure with relatively low terminal pressureat eX- haust for a given out off and cylinder temperature, and at thesame time attain a most important result by securing a minimum clearanceboth in the cylinder and the connecting ports, which will providecompres sion suflicient for the proper cushioning and efficientoperation of the piston within the cylinder.

The cylinder and steam-chest with the connected live steam and exhaustports are also constructed and arranged so as to pre vent to thegreatest extent radiation of heat, thereby tending to hold all the heatunits of the live steam pressure and the mean cylinder temperature atthe highest degree attainable, and reduce condensation in the cylindersteam chest, and connected ports to a minimum.

The cylinder and steam chest are provided with connecting live steam andexhaust ports which in length, condensing and frictional surfaces arereduced to a minimum and these are so arranged that the passagesSpecification of Letters Patent.

Application filed January 9, 1908.

Patented June *7, 1910.

Serial No. 409,974.

within the space surrounded by the exhaust steam passages.

One of the specific purposes of the invention is to provide a noveloperating mechanism for a compression controlling or regulating valvewhich will open said valve for exhaust simultaneously with or a littlelater than the main valve but cause the same to close for compressionmuch later than the main valve.

A further specific purpose is to provide a novel form of main valve, thesame being built up in a way to make an exceptionally light and at thesame time strong construction, the parts thereof being preferably ofcast steel. Means are provided whereby said valve is balanced and it isat the same time arranged to readily recede from its seat or float whiledrifting when used in connection with locomotive cylinders havinglow-clearance and compression regulating valves.

Other features of improvement in detail, will appear from the followingdescription of the preferred embodiment of my invention.

My invention comprises the novel features of construction and relativearrangement of parts which will be hereinafter described andparticularly pointed out in the appended claims.

Reference is had to the accompanying three sheets of drawing, forming apart of this specification, in which similar reference charactersindicate corresponding parts throughout the several figures.

Figure 1, is a central longitudinal section and development on line 11,Fig. 2, the compression regulating valve being shown in elevation; Fig.2, is a transverse and normal section on line 22, Fig. 1; Fig. 3, is anapproximately central transverse section on line 33, Fig. 4, thevalvesand pressure plates being removed; Fig. 4, is partly a section on line4-4, Fig. 3, and partly an elevation from the same plane; Fig. 5, is asection on line 55, Fig. 4; Fig. 6, is a section on line 6 6, Fig. 5;Fig. 7, is a plan view of one-half of the upper sides of the maindistribution and compression regulating valve; Fig. 8, is a plan view ofone-half of the unleading the live steam to the cylinder are der side ofthe main distribution valve; Fig.

9, is a side view, partly in section, of the con nected maindistribution valve and compression regulating valve; Fig. 10, is a frontview of 1* 8, with valve rod removed; Fig. 11, is a section on line 1111of Fig. 9; Fig. 12, is a perspective view showing the relation of thepacking strips of main valve; and Fig. 13, is a detail view showing asection of the divided valve stem for holding the dash pots ofcompression regulating valve. Fig. 14L, is a sectional view of one endof the main valve showing arrangement of reinforcing rods.

In said drawings, 1 is a cylinder which is provided with the usualheads, stuffing box, and other essentials which need not be furtherdescribed as they form no part of the i11- vention.

2 is a piston having connected therewith a piston rod 3, which isprovided with a crosshead (not shown) the same being supported andguided in a well known manner.

t is a steam chest located immediately adjacent and preferably above thecylinder, and extending over a considerable part of the peripherythereof, thus providing a jacketing effect. The wall 5 between the cylinder and steam chest is made of suflicient thickness to properly supportthe valve and withstand the pressure to which it may be subjected.

6 is a pressure plate having lateral lugs thereon through which bolts 7pass to secure said pressure plate to the steam chest. A suitable cover8 for the steam chest is fitted to the same and as shown such cover ismade integral with the pressure plate, the necessary passages being ofcourse formed therebetween. The pressure plate 6 is preferablyconstructed with double walls provided with intervening air spaces forthe purpose of insulation, and said walls are braced by suitable strutsso as to attain great stiffness without excessive weight.

9 is the main valve the same being preferably rectangular in outline andof a built-up construction hereinafter more particularly referred. to.Said main valve is adapted to be reciprocated in a corresponding shapedspace 9' therefor in the steam chest and to closely fit upon the seat 9provided therefor in said steam chest. Such reciprocation is imparted asusual by a stem 10 from any ordinary valve controlling means (notshown).

The valve 9 is preferably of the rectangular type formed with two endpieces or heads 11-11, which with suitable packing form a tight ointwith the walls of the pressure plate and register with and control theports 1212. Said packing strips see Figs. 8, 10 and 12, are preferablymade in three sections, 42, 13, and 44, +12 resting in of the valve.

the groove. on the top of the valve, while the sections 13 and 4% are inthe side grooves The contiguous ends of the sections are so formed asindicated in F 10 and 12 that they look each other in position. Sections13 and 44 have registering slots 45 through which passes a pin 46, seeFigs. 8 and 10, thereby holding them in place.

13 is a hollow spool forming a central tie section and as shown theactuating stem 10 has a reduced extension passing loosely through theinner end of'said spool and secured to the outer end thereof by asuitable shoulder and nut thereon. This arrangement enables the valve tobe raised or recede from its seat slightly when compression takes placein the cylinder.

As supports for-1 the end pieces 11, additional to the central spool 13,lateral tie rods 14: are provided extending from end to end of the valveand suitably secured to the heads 11.

18, 13 are extensions on the valve near the inner sides of the endpieces or heads, which form riding-shoes or auxiliary bean ing surfacesin addition to that provided for the valves proper and these are at adistance from the inner sides of the valve ends not less than the widthof the ports, and provided with recesses 17, and 18 on their under sidesas shown in Fig. 8, for the purpose of containing and evenlydistributing the lubricant. By this means an abundant sliding surface issecured which prevents rapid wear and at the same time as the ridingshoes are drawn back far enough on the valve seat to reach that positionwhich is well lubricated, they will act as distributers and furnish thevalve seats with lubricant which they would not otherwise receive forthe reason that the valve faces especially in short travel do not reachthe oiled position of the valve seat. Furthermore the steam usuallyblows off the oil from the valve seat near the ports in entering thecylinder and by the above arrangement and construction of riding shoesthe oil is constantly replenished.

15 and 16 are transverse intercepting pas sages in the lower side of thevalve ends 11 and which extend nearly the entire width of the valve. 15and 16 are channels connecting with said passages 15 and 16 and extending upward to the top of the valve where they open into the spacesbetween the packing strips at the end of said valve. The purpose ofthese passages, as fully explained in my cO-pending application SerialNo. 394,517, filed September 25, 1907, is for the intercepting of thesteam when passing under the valve when the port is uncovered, andtherefore allowing the steam to pass up the channels 15 and 16 andinstantly equalize the pressure between the upper and lower sides of thevalve. By this simple construction and arrangement it will be seen thatI have not only devised a valve that will float, but one that will be atthe same time perfectly balanced, which especially adapts the engine forlocomotive and other high speed Work.

19 and 20 are the auxiliary exhaust or compression regulating valveswhich in the embodiment shown are of the piston type, though it will beunderstood that other types may readily be substituted. Said valvescontrol the short auxiliary ports 21 and 22 and as will be seen byreference to Figs. 1, 3 and 41 these valves are situated adjacent to theinner portion of the cylinder and control passages connecting with theoutside exhaust passages 23 which lead to the petticoat pipe connection24.

25 is the live steam pipe connection, which by means of passage 25 leadssteam into the space 26 of the valve chamber between the two heads 11,11 of the main valve and surrounding the central and lateral tie members13 and 14: thereof. It will be observed that the live steam and exhaustpassages are separated by air spaces thus affording a better insulation,it being further arranged so that the live steam is on the inside andthe exhaust passages on the outside thus protecting live steam from thecooling action of the atmosphere.

From the description thus far it will be apparent that by my improvedarrangement and construction of live steam ports and exhaust, I havedevised a cylinder in which the length of the ports is reduced to aminimum, thereby reducing the clearance, radiating surfaces, thefriction of the steam in passing to the cylinder and at the same timepermitting the short straight ports to be readily and easily cleaned.

It will be further noticed that by my improved built up construction ofmain valve the same is made light and very strong and that the severalparts thereof can be provided and assembled with facility, I preferablymake these valve parts of cast steel.

I will now proceed to describe the improved construction of auxiliaryexhaust or compression regulating valve, and the novel actuatingmechanism therefor, which feature constitutes essential elements ofnovelty in the presentcase.

The compression regulating valve comprises the two end barrels or valvesections 19 and 20 connected together by a stem 31, which stem in itsmiddle section 36 as indicated in Figs. 7, 9 and 13, is divided wherebysuitable seats are formed for the two dash pots 32 and 33 which aresecured thereto by rivets 34. The distance between the two dash pots canbe adjusted or regib lated by removing or grinding away or add ing aportion of metal at 35 on opposite sides of the middle section 36.Reciprocating in said dash pots 32 and 33 are the two connected pistons37 and 38 which are connected together by a sleeve 39 through which isbored a hole 40.

An arm 28 is provided with flanges 29 said flanges being adapted to besecured to the central spool 13 of the main valve by means of bolts 30.Said arm 28 is attached to the two pistons by passing loosely throughthe opening 40 in said sleeve 39, as shown. The sleeve 39, see Figs. 7and 11, is provided on each side with a lug or projection 41 which lugsare squared at their ends and adapted to engage the inner walls of thesides of the middle section 36 thereby prevent-ing the pistons 37 and 38from turning.

The operation of my improved mechanism will be readily understood fromthe fore going description.

The live steam under the main valve 9 and between its ends 11, 11,passes by means of the passages between the riding shoes 13 and the endsof the valve through the short port 12 into the cylinder back of thepiston 2 when the same is forced to the other end of the cylinder. Aftercompletely uncovering the ports 12 the main valve returns and cuts offat a time regulated by the valve gear, the expanded steam at the otherend of the cylinder having exhausted through the other port 12,uncovered by the other end of the main valve. This movement of the mainvalve, is through the arm 28 transmitted to the auxiliary exhaust orcompression regulating valve stem 31, and with a predetermined amount oflost motion is imparted to the valve barrels 19 and 20 which control theauxiliary exhaust passages 21 and 22. It will thus be apparent that thesaid auxiliary exhaust ports 21 and 22 will be closed after the mainexhaust through ports 12 or 12 has been closed by the main valves 11. Bythis arrangement of pistons and actuating mechanism the auxiliaryexhaust valves will open simultaneously with, or a little later, thanthe main valve, but are made to close much later than the main valve forcompression and hence effect a more eflicient distribution of the steamby avoiding unnecessary back pressure due to the too early closing ofthe main valve and at the same time having under absolute control theregulation of the compression independent of the main valve, whereby theclearance of the ports and cylinder may be reduced and consequentlyeffect a great saving of steam.

To vary the time of closing the auxiliary exhaust passages one simplyproperly adjusts as above indicated, the distance between the closedends of the dash pots 32 and 33 either by taking away or addingthickness of metal at 35 when the required minimum compression for thesmooth running of the engine is effected.

It will be obvious that my invention may be applied with equal advantagefor use with expansible fluids other than steam.

It will also be apparent that numerous changes may be made in details ofmy improved engine and in the specific means for operating and adjustingthe valves without affecting the essential features, and while I have inthe foregoing specification described what now appears to be apreferable embodiment of the invention, yet it will be obvious to thoseskilled in the art that this specific embodiment may be modified in manyways and still come within the purview of the appended claims, wherein Ihave pointed out the distinguishing characteristics of my saidinvention.

Referring especially to Figs. 7, 8, 11 and 14, it will be seen thatthere is inserted and cast integral with the main valve 9, two

wrought iron rods 47, 17, which have their ends 48, 48, curved. Thesetwo iron rods 17 are placed 111 the mold before castlng the main valveand being wrought iron cool slower than the cast iron section of thevalve 3 l I l l and hence when the cast iron has solidified andcontracted to its maximum the wrought lron rods are still in the stateof contraction and hence by means of the curved ends 18,

tightly grip the ends of the valve 9 and draw them toward the center.These rods 17 act as auxiliary rods to rods l-it and in case any I oneof the two rods 14: break the rods -it7 wlll tightly hold the valvetogether. If desired the rods 141-, may be omitted but are used in orderto make the valve 9 as light as possible I main valve in said steamchest controlling the admission and exhaust through the steam ports, acompression regulating valve controlling the auxiliary ports, and a dashpot connection from said main valve to said auxiliary exhaust valve saidconnection being within the steam chest.

2. A steam engine comprising a cylinder, short admission and exhaustports leading thereto, a main valve adapted to control said ports, shortauxiliary exhaust ports leading from the-cylinder, an auxiliary exhaustor compression regulating valve to control said auxiliary ports, and adash pot connection from said main valve to said auxiliary valve saidconnection being inclosed Within the valve casing.

3. A steam engine comprising a cylinder, short admission and exhaustports leading thereto, a main valve adapted to control said ports, shortauxiliary exhaust ports leading from the cylinder, an auxiliary exhaustor compression regulating valve to control said auxiliary ports, and adash pot connection from said'main valve to said auxiliary valve, saidconnection being inclosed within the valve casing and including a lostmotion device.

L. A steam engine comprising a cylinder, a steam chest, admission andexhaust ports connecting the steam chest and cylinder, auxiliary exhaustports connecting the cylinder with the main exhaust, a main valve insaid steam chest controlling the admission and exhaust through the steamports, an auxiliary exhaust compression regulating valve controlling theauxiliary exhaust ports and an adjustable or variable dash pot and lostmotion connection from said main valve to said auxiliary valve, saidconnection being within the steam chest.

5. A steam engine comprising a cylinder, main admission and exhaustports leading to the ends thereof, main valves adapted to control saidports, auxiliary exhaust ports leading from the cylinder, auxiliaryexhaust or compression regulating valves to control said auxiliaryexhaust ports and a connection from said main valves and intermediatethe same, to said auxiliary exhaust or compression regulating valves andintermediate the same, said connection including a dash pot and a lostmotion device.

6. A steam engine comprising a cylinder, main admission and exhaustports thereto, main valves to control said ports, auxiliary exhaustports to said cylinder, auxiliary exhaust or compression regulatingvalves to control said auxiliary ports and an intermediate connectionfrom said main valve to said auxiliary valves, the same comprising anarm secured to the main valve stem and having a dash pot and lost motionengagement with the auxiliary valve stem said parts being inclosedwithin the valve casing.

A steam engine comprising a cylmder, main admission and exhaust portsthereto, main valves to control said ports, auxiliary exhaust ports tosaid cylinder, auxiliary exhaust or compression regulating valves tocontrol said auxiliary ports, a stem on which said auxiliary valves aremounted and a dash pot and lost motion connection from said main valvesto said auxiliary valve stem.

8. A steam engine comprising a cylinder, main admission and exhaustports thereto, main valves to control said ports, auxiliary exhaustports to said cylinder, auxiliary eX- haust or compression regulatingvalves to control said auxiliary exhaust ports, a stem on which saidauxiliary valves are mounted, adjustable dash pots on said stem, and anintermediate connection from said main valves to said dash pots on saidauxiliary valve stem.

9. A steam engine comprising a cylinder, main admission and exhaustports thereto, main valves to control said ports, auxiliary exhaustports from said cylinder, auxiliary exhaust or compression regulatingvalves to control said auxiliary exhaust ports, a stem on which saidauxiliary valves are mounted, means for adjustably mounting dash pots onsaid stem, and means for giving relatively timed movements to said mainand auxiliary valves.

10. A steam engine comprising a cylinder, main admission and exhaustports thereto, main valves to control said ports, auxiliary exhaustports from said cylinder, auxiliary exhaust or compression regulatingvalves to control said auxiliary exhaust ports, a stem on which saidauxiliary valves are mounted dash pots adjustably seated on said stem,and means for imparting relatively timed movements to said main andauxiliary valves.

11. A steam-engine comprising a cylinder, a steam chest, a valve-seat inthe steam-chest adjacent to the wall of the cylinder, admission andexhaust ports passing through the wall and valve-seat and connecting thesteamchest with the cylinder, a slide valve on said valve-seatconsisting of a central section, end pieces having surfaces parallelwith the line of travel of the valve and at right angles to the centralsection and which control the short steam-ports, back on said endpieces, a pressureplate of corresponding form and covering theslide-valve, means for conducting the live steam under thepressure-plate and between the end pieces of the valve, auxiliaryexhaust-ports connecting the cylinder with the main exhaust and acompression-regulating valve controlling the auxiliary exhaust ports.

12. A steam-engine comprising a cylinder, a steam-chest, a valve-seat inthe steam-chest adjacent to the Wall of the cylinder, admission andexhaust ports passing through the -wall and valve-seat and connectingthe steam-chest with the cylinder, a slide-valve on said valve-seatconsisting of a central section, end pieces having surfaces parallelwith the line of travel of the valve and at right angles to the centralsection and which control the ports, tie rods connecting end pieces ofvalve, a riding strip or surface provided at each end of the valve at adistance from the inner edges of the valve and pieces not less than thewidth of the ports, a pressureplate covering the piston slide-valve,means for conducting the live steam under the pressure-plate and betweenthe end pieces of the valve, auxiliary exhaust-ports connecting thecylinder with the main exhaust and a compressioil-regulating valvecontrolling the auxiliary exhaustports.

13. A steam-engine comprising a cylinder, a steam-chest, a valve-seat inthe steam-chest adjacent to the wall of the cylinder, admission andexhaust ports passing through the wall and valveseat and connecting thesteam-chest with the cylinder, a slide-valve on said seat consisting ofa central section, end pieces having surfaces parallel with the line oftravel of the valve and at right angles to the central section and whichcontrol the ports, means for balancing the steampressure on the endpieces, a pressure plate covering the slide-valve, means for conductingthe live steam under the pressureplate and between the end pieces of thevalve, auxiliary exhaust-ports connecting the cylinder with the mainexhaust and a compressionregulating valve controlling the auxiliaryexhaust-ports.

14. A locomotive steam-engine comprising a cylinder, a steam-chest, avalve-seat in the steam-chest adjacent to the wall of the cylinder,admission and exhaust ports passing through the wall and valve-seat andconnecting the steam-chest with the cylinder, a slide-valve 011 saidseat consisting of a central section, end pieces having surfacesparallel with the line of travel of the valve and at right angles to thecentral section and which control the ports, tie rods under contractionconnecting the end pieces, means for permitting the piston slide valveto recede from its seat or float, a pressure-plate covering the pistonslide-valve, means for conducting the live steam under thepressure-plate and between the end pieces of the valve, auxiliaryexhaust-ports connecting the cylinder with the main exhaust and acompression-regulating valve controlling the auxiliary exhaust-ports.

In testimony whereof I aiiix my signature in presence of two witnesses.

JAMES B. ALLFREE. Witnesses:

FRANcIs S. MAGUIRE, W. E. SoHoENBoRE.

